Psychotherapy is one of the more effective ways to treat depression, but there’s a hurdle: getting people to seek out and stick with care. A new study suggests that for some patients, receiving therapy by telephone, instead of face-to-face on the therapist’s couch, could be a solution.

In the most definitive study to date comparing face-to-face cognitive behavioral therapy (CBT) to that given over the phone, researchers found that phone-based therapy was just as effective as that given in a therapist’s office, and that more patients relying on phone sessions stuck with their therapy.

The findings address the lingering skepticism among therapists over whether phone-based treatments can actually help, says study author David Mohr, director of the center for behavioral intervention technologies at Northwestern University, and suggest that especially for patients with significant hurdles to face-to-face therapy, treatment by phone is a viable option. CBT is only effective if people stick with it, and up to 50% of depressed people don’t keep up with psychotherapy.

Mohr and his team recruited 325 people with depression, and randomly assigned them to 18 weekly sessions of CBT either in a therapist’s office or over the phone with similarly trained therapists. Significantly fewer people dropped out of the phone-therapy group: by the end of the 18 weeks, only 21% (or 34) of the phone-based therapy patients had stopped their sessions, while 33% (or 53) of the face-to-face patients had.

Both groups of patients improved equally during the course of their treatment, but researchers continued to monitor the participants for six months after therapy ended. By that point, those who had received face-to-face treatment were doing slightly better, reporting fewer symptoms of depression.

Mohr believes that the difference doesn’t necessarily suggest that phone therapy is less effective, but rather that the phone-based group ended up including more severely depressed patients. Although both the phone and face-to-face therapy groups likely started out with similar proportions of mild and severely depressed people, it’s possible that more of the severely affected patients dropped out of the face-to-face group, leaving fewer participants with hard-to-treat disease. Perhaps these patients, who didn’t come to office therapy, were more easily tracked down by phone. “We heard from the therapists in the phone-based group that when they called, some of the patients had forgotten their sessions, or that they had to be woken up from a nap,” he says.

Mohr and his colleagues are now studying whether this is true or whether in-person therapy is more effective in the long-term.

The results, published in the Journal of the American Medical Association, suggest that phone options may be a valuable way to bring the benefits of psychotherapy to more depressed patients. Already, in a recent survey among members of the American Psychological Association, 80% of therapists acknowledged that they deliver some of their care over the phone. But in order to maintain psychological improvements, says Mohr, patients should be monitored frequently for remission.

“I think this study is definitive in saying that face-to-face contact is not really necessary,” he says. “I don’t think this means that telephone psychotherapy replaces face-to-face therapy, but it means they are certainly interchangeable, and that phone therapy is not a second-rate treatment for patients with depression.”

Alice Park is a writer at TIME. Find her on Twitter at @aliceparkny. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.